You could definitely come up with a scheme whereby your calculator was powered for a solar cell array. You could even designed it to produce exactly the 6V that your calculator is expecting when fully illuminated. The bigger problem is that solar cells' output fluctuates wildly, so your best bet would be to use rechargeable batteries, a charge controller, and a set of solar cells to charge the batteries (which in turn power the calculator). Do you have any/much experience with electrical engineering projects such as this?

You could definitely come up with a scheme whereby your calculator was powered for a solar cell array. You could even designed it to produce exactly the 6V that your calculator is expecting when fully illuminated. The bigger problem is that solar cells' output fluctuates wildly, so your best bet would be to use rechargeable batteries, a charge controller, and a set of solar cells to charge the batteries (which in turn power the calculator). Do you have any/much experience with electrical engineering projects such as this?

I don't really have any experience with smaller scale electronics, but i know basic circuitry (e.g. resistors, capacitors, diodes). I picked up 4 rechargeable AA's a while back, and haven't used them for anything important, so i figured that i could hook up the solar panel to charge them. The solar panel has a maximum voltage output of 6v, and if i hooked it up in parallel to the 4 AA's, 6 volts would always be going to the calculator since the higher voltage in a parallel circuit takes over. I just really want to know if this will fry my calculator, because my last (school issued) calculator died via electric shock, and I don't want to fry another one. Please share any ideas you think could improve this project, and let me know if you think it will fry my calculator :).

Have you considered a buck boost regulator and a super capacitor?
The buck boost regulator will protect the calculator from both too low and too high voltage. When the voltage is too low it will boost the voltage to the proper level. When the voltage is too high it will regulate the voltage to the proper level. The super capacitor will store excess power in bright sunlight then when there is not enough sun the energy stored in the capacitor will be used to power your calculator.

While the LM317 would be good to regulate a reliable source down to 6V for the calculator, it would be a very poor choice for solar charging, unfortunately. The LM317 is a linear regulator, which is bad for two reasons:
1) It requires an input voltage at least ~1.5V higher than the target voltage. For a 6V output, it must receive at least 7.5V. For a solar panel array, this means that you would need at least 7.5V worth of solar cells, and it would only work in full, direct sunlight.
2) Linear regulators dump extra power as heat. If you provide it with, say, 9V, it will dump (9-7.5V)*I as heat through its metal fin. This could be solved by using a switching regulator, but (1) will still apply for a switching regulator.

As ProgrammerNerd suggested, a buck-boost regulator would be far better-suited to this sort of design, and a super capacitor in place of rechargeable batteries is actually not a bad idea at all.

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